Sound Environment as a Global Issue

Application of ISO 2631-1 (1997) for evaluating discomfort from

whole-body vibration: verification using field and

laboratory studies

Dr. Ykä Marjanen and Dr. Neil J. MansfieldLoughborough University, UK

Sound Environment as a Global Issue

The goal of the research

Provide a practical method for engineers to minimize the negative effects of vibration

Sound Environment as a Global Issue

Effects of vibration exposure

HealthHealth

Dis-comfor

t

Dis-comfor

t

Back painLong term effectsMany variablesComplex cause-effect relationship

More psychologicalImmediate feedbackLess variablesSimpler cause-effect relationship

Sound Environment as a Global Issue

Current knowledge

Sound Environment as a Global Issue

Current knowledge

Little information on effect of time

Little information on the variability of sex and size of a person

Few studies on combining the axes

Few studies on determining best averaging method

One study of using all 12 axes in field

One study to determine correlation in field

Sound Environment as a Global Issue

Evaluation of ISO 2631-1

• Is the standard method valid?

• What is best approach of using it?

• How well does it predict discomfort?

Sound Environment as a Global Issue

Which axes dominate in field

Sound Environment as a Global Issue

Validating the standard method

• Seat translational axes are enough for prediction

• Frequency weighting works

• R.m.s. is better than r.m.q.

• Multiplying factors do not work well

Sound Environment as a Global Issue

Improving the standard method

Sound Environment as a Global Issue

Simplifying the guidance on using the method

• Measure three translational axes from the seat

• Use the r.m.s. method to average them

• Combine to a single value using 1.4 multiplying factors

• Compare two or more setups in same environment

Sound Environment as a Global Issue

Concluding the necessary changes and research for improving the

method• Getting rid of the options for using the

additional axes

• Providing guidance on how to interpret the results

• Providing a method to optimize multiplying factors for different environments